/Engine/Plugins/Runtime/GeometryProcessing/Source/DynamicMesh/Public/Sampling/MeshImageBakingCache.h
Iterate over valid samples in the Occupancy map to find "holes", ie pixels where no valid sample could be computed according to IsValidSampleFunction. This can be used after a bake to find locations where the baked map needs to be repaired as a post-process (eg using image infilling/etc), which can produce better results than (eg) using a "worse" sampling strategy to guarantee some non-garbage result (eg Nearest-point sampling)
void FindSamplingHoles ( [TFunctionRef](API\Runtime\Core\GenericPlatform\TFunctionRef)< bool(const [FVector2i](API\Runtime\GeometryCore\FVector2i) &)> IsValidSampleFunction, [TArray](API\Runtime\Core\Containers\TArray)< [FVector2i](API\Runtime\GeometryCore\FVector2i) > & HolePixelsOut, bool bParallel ) const